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ATP*

"Mark Rand" wrote in message
...
On Thu, 15 Nov 2007 01:39:47 -0800 (PST), wrote:

An electrician friend explained the wiring codes to me thus.....

"it doesn't matter if your a nuclear scientist who designs and builds
power stations and is perfectly capable of wiring something up - YOU
know how you've done it, what the circuit will bear, and if you splice
extra outlets onto a run, YOU will know NOT to overload it. Thats fine
as far as it goes.

BUT - eventually, someone else will live in that property, they will
have no knowledge of what you have done, what loading precautions to
take. So, inadvertently, you have provided a potentially dangerous
installation....

This is why there are standards codes...."

Andrew VK3BFA.

Actually, I find that one hard to understand... The protection on the
circuit
(fuse, MCB etc) should be rated to protect the components in the circuit.
Therefore how can one create a dangerous situation by overloading it?

Mark Rand
RTFM

You're assuming that the overcurrent device is going to operate flawlessly
at some future point. Good design and practice minimizes the chances that
the circuit will be loaded beyond its capacity. Multiple safety factors are
built in, and much of the code is written due to actual incidents reported
to the NFPA.